The present invention relates to wireless communication systems supporting communication of packet data which include a core network and a number of radio networks, and particularly it relates to the control of radio networks, e.g. via radio network control means, by packet data support nodes of the core network. The invention also relates to a packet data support node in a communication system supporting communication of packet data and to a method of controlling, in a communication system supporting communication of packet data, connections between user stations and/or connections between user stations and external packet data networks.